Backpack



FIG. 1 is a perspective view including a front, top and one side of the backpack;

FIG. 2 is a front elevation view of the backpack of FIG. 1;

FIG. 3 is a rear elevation view of the backpack of FIG. 1;

FIG. 4 is an opposite side elevation view of the backpack of FIG. 1;

FIG. 5 is a side elevation view of the backpack of FIG. 1;

FIG. 6 is top plan view of the backpack of FIG. 1;

FIG. 7 is a bottom plan view of the backpack of FIG. 1; and,

FIG. 8 is a front elevation view of the backpack of FIG. 1 shown in an open and flat condition. 

CLAIM The ornamental design for a backpack, as shown and described. 